Downregulation of ABCG2 expression in glioblastoma cancer stem cells with miRNA-328 may decrease their chemoresistance.

ABCG2, which encodes an ATP-binding cassette transporter protein, is associated with the phenotype of cancer stem cells and is used to define the pluripotential side population cells by flow cytometry and slide-cytometry. MicroRNAs control a wide array of biological processes (e.g., cell differentiation, proliferation and apoptosis) whose dysregulation is a hallmark of cancer. MicroRNA-328 (miR-328) is underexpressed in many cancers including glioblastoma multiforme and contributes to tumor resistance to chemotherapy. ABCG2 is associated with multi-drug resistance and is also highly expressed in glioblastoma. Some preliminary studies have shown that ABCG2 is the target gene for miRNA-328. Thus, we hypothesize that modulating ABCG2 expression by targeting miRNA-328 in glioblastoma cancer stem cells could represent a promising strategy for therapeutic manipulation to increase the efficacy of chemotherapeutic agents for glioblastoma, a highly lethal type of cancer.